<html>
Test for boolean attributes

<input type="checkbox" name="foo" checked="1" />
<input type="checkbox" name="foo" tal:attributes="checked checked" />
<input type="checkbox" name="foo" tal:attributes="checked notchecked" />
<input type="checkbox" name="foo" tal:attributes="checked notchecked" checked="1" />
<input type="checkbox" name="foo" tal:attributes="checked checked" checked="1" />
<input type="checkbox" name="foo" tal:attributes="checked checked; name 'bar'" checked="1" />
<input type="checkbox" name="foo" tal:attributes="checked notchecked; name 'bar'" checked="1" />
</html>
